Combined passive acoustic and video monitoring of coral reefs to better understand reef soundscapes and multi-species interactions

Abstract

A detailed understanding of ecological soundscapes provides a window into ecosystem state that might otherwise go undetected. Rather than consider acoustic emissions of a particular species, a top down ecosystem acoustics point of view gives potentially valuable insights to reef ecosystem function. Simultaneous passive acoustic and video data were collected from coral reefs off the Kona Coast of Hawaii in January 2019 during a soundscape experiment. Frequent interactions between fish species as well as collective behaviors are identified and tracked by applying computer vision to video data. Comparison relating video data to acoustic data allows assessment of the same behaviors as simultaneously reflected in directional passive acoustic data. Collective consideration of acoustics and video offers insight into acoustic signatures of particular soniferous communities and behaviors amongst and between reef species. Machine learning applications match patterns between fish trajectories in videos and the sound field as received by a directional antenna. The relative level of biological activity and presence or absence of particular behaviors provides key data in the effort to understand coral reef ecosystem state.